Converting Shield from .40 to 9mm

In the past few years the S&W Shield has become one of the more popular pistols for concealed carry or just general defense, it’s small, light, slender and in 9mm controllable. But what if you find yourself in the situation I found myself in, with a Shield in 40 S&W. The 40 S&W Shield is still light, small and slender but as for controllable well that’s where the larger caliber loses points against the 9mm.

Conversion barrels abound for many handguns, the 40 S&W Glocks and standard M&Ps can be converted to 9mm and .357 Sig with a simple barrel swap and my XD 40 currently has a 9mm barrel in it. But the Shield has suffered a surprising lack of conversion barrels. This is somewhat surprising given that the factory 40 and 9mm barrels have nearly identical external dimensions. I say ‘nearly identical’ because there is a negligible difference in the rear of the barrel between the two.

Well I have good news, unless you’re in California like I am then I have somewhat good news. This month, June 2017, Lone Wolf released a couple of lines of 9mm S&W Shield barrels. These come in standard and threaded. The threaded cannot be used in California, apparently or Legislature believes that having a threaded barrel in a pistol will make you involuntarily kill a bus load of nuns on their way to feed the homeless. But we can still use the standard barrel right? Well… not exactly.

One of the other ‘gifts’ we Californians have been given by our all-knowing Legislature is a list of ‘safety features’ required on all handguns. None of these features make a handgun any safer but they should do provide a nifty way to limit the models of handguns California citizens can buy. Then again when has ‘gun control’ ever been about safety? One of the requirements is a Loaded Chamber Indicator (LCI) meant to give a visual and tactile indication of a loaded chamber. In the case of the S&W Shield this is a slot cut in to the top of the slide with a spring loaded lever that pops up when there is a round in the chamber.

A side by side comparison of a standard Shield barrel and a CA Shield barrel shows a difference in construction between the two. The standard barrel has a dished half circle cut in to the hood and the CA Shield barrel has a slot cut in to the rear of the barrel hood for the indicator lever. The new Lone Wolf barrels have a standard barrel hood with the dished half circle meaning they will not work in a stock CA Shield slide. The LCI lever would not allow the slide to properly go in to battery. California’s asinine requirements have stifled my ability to convert my 40 S&W Shield in to a 9mm S&W Shield. Or have they…

As onerous as California laws are they have had an interesting side effect of inspiring some rather ingenious methods of complying with the laws while still being able to own and use our firearms. In this spirit I started looking at ‘How can I make this work without having to do any modifications to the new barrel?” The problem was that the LCI Lever would impede the barrel hood preventing the gun from going in to battery. But what if the lever was not there? I could remove the LCI but that would leave a large slot in the top of my slide and a hole where the LCI spring sits.

APEX Tactical provides the answer, the make two replacement parts for the S&W Shield LCI. One is a low profile LCI which retains the LCI but reduces its height the other is a ‘no profile’ LCI filler. The ‘no profile’ LCI not only fills the slot in the slide it removes to portion of the LCI lever that protrudes in to the barrel hood making the slide flush where it mates with the barrel hood. Replacing the LCI is simple, a small hammer, a roll pin punch and about four minutes is all you need.

Replacing the LCI did the job, the APEX Tactical ‘no profile’ LCI allowed the Lone Wolf AlphaWolf Shield barrel to drop right in to my 40 S&W Shield. Lock up is tight and so far running rounds through it by hand has been flawless. Next is a range trip for a trial by firing where I suspect it will perform without a problem. For just a hair over $150 my S&W Shield has become a dual caliber handgun. One interesting side effect has been that it feels lighter in the hand and pocket loaded with 9mm rounds then it did loaded with 40 S&W rounds.